WASHINGTON – U.S. investigators looking into the May 17 Connecticut commuter-rail crash haven’t yet found a clear cause.

The fact a broken rail became the most immediate suspect speaks to years of deferred maintenance that have left trouble spots throughout a Washington-Boston network that carries more than 700,000 people a day and dates to the 1800s.

“We are eating our assets alive,” Joseph Boardman, CEO of Amtrak, said in an interview May 21 after testifying at a congressional hearing.

Tracks maintained by the intercity passenger railroad and states along the most densely populated part of the U.S. carry half of U.S. rail traffic. Amtrak now accounts for 76 percent of the air and rail trips between New York and Washington, up from 37 percent in 2000, according to the Northeast Corridor Commission, a body Congress created in 2008 to assess the system’s most critical infrastructure needs.

Between New York and Boston, the share has increased from 20 percent to 54 percent.

“One cracked rail is making it extremely inconvenient for thousands and thousands of commuters,” said Robert Puentes, senior fellow at the Brookings Institution’s Metropolitan Policy Program in Washington. “That has a drag on the overall metropolitan region. This is an infrastructure that needs to be brought up to a state of good repair.”

Ownership hodgepodge

Unlike with highways, which count almost all Americans as a constituency, and aviation, which is backed by the airline industry and a powerful trade group, Amtrak – the biggest player along the 457-mile Northeast Corridor – has stood almost alone as it asks Congress for money to cover operating shortfalls and maintain its tracks.

Formed by Congress in the early 1970s to take over unprofitable passenger operations from freight railroads, Amtrak owns the track between Washington and New Rochelle, New York, and from New Haven, Connecticut, to the Massachusetts border. Metro North Railroad and the state of Massachusetts own the other sections.

The corridor hosts commuter lines in Maryland, Delaware, Pennsylvania, New Jersey, New York, Connecticut, Rhode Island and Massachusetts as well as slower freight trains that add to the wear and tear on rails.

1889 bridge

Hundreds of bridges and tunnels are more than 100 years old, according to the corridor commission. Five bridges in Connecticut built between 1889 and 1907 need to be replaced, with costs exceeding $1.6 billion, the commission said.

Portions of the electrical system date to the 1930s, including Connecticut substations that rely on oil-filled circuit breakers.

As service demands in and around New York increase, Amtrak has less opportunity to spend time doing maintenance in the area, Boardman said. The railroad can only take the six tunnels under New York out of service for a total of 55 hours each week to maintain them, he said.

Because Amtrak and commuter rail lines share tracks, delays on one can cascade through the system, Connecticut state transportation commissioner James Redeker testified at an April Senate hearing. All major segments of the system are at or close to capacity, making service increasingly susceptible to disruptions, he said.

In last week’s wreck, a section of the eastbound track “fractured at a rail joint” and is “of interest” to NTSB investigators, the board said in Twitter postings May 18.

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